In copending application Ser. No. 07/394,775, filed Aug. 16, 1989, "Power Distribution System for Modular Furniture Units", owned by the assignee of the present invention, a power distribution system is described and claimed which includes a power block having an insulating housing containing ten vertically aligned, parallel bus bars to which circuit connections are established by various plug-in components of the system. The plug-in components may comprise a connector for a jumper cable interconnecting the power distribution systems of adjoining furniture units such as wall panels or a connector through which power is supplied to the furniture or panel distribution system from the base power distribution system or it may comprise an outlet unit containing receptacles for the plugs of power cords attached to electrical appliances.
In the distribution system of the referenced application, the bus bars are flat and closely spaced to reduce the height of the power block, so that the power block can be fit into the space available in furniture units of existing design. The close spacing of the bus bars requires that the male contacts of the plug-in components used with the system be of low profile to enable the contacts to be arranged in a columnar pattern of a height compatible with the height of the power block while still preserving adequate spacing between the adjacent contacts of the column.
One type of prior art contact that can be fashioned with a profile of a height corresponding to the height of the profile of the contacts of the present invention is the single beam cantilever type contact. Such a type of contact requires that the fixed end of the contact beam be rigidly supported in the housing of the contact in order to counter the reaction force developed at that end of the beam when the free end of the beam is deflected. Such a requirement demands that the structure supporting the fixed end of the contact beam be dimensionally stable with time if normal pressure by the contact upon the conductor engaged is to be maintained throughout the life of the contact.
Conventional contact housings are molded from an insulating plastic material. As is well known, objects molded from plastic have a tendency to change dimensionally due to creep of the plastic with age. This tendency is amplified when the object is subjected to continuous forces in an environment of elevated temperature.